This invention relates to liquid applicators having particular utility in the field of antiseptic skin surface preparation. More particularly, this invention relates to articles and methods useful in applying pre-operative surgical scrubs or paints to skin.
Antiseptic preparation of patient""s skin for surgery conventionally includes a 3-10 minute scrubbing of the affected area with a soap solution followed by the application of a water-soluble antiseptic paint solution. These solutions are generally applied with saturated sponges attached to a blade or held with forceps. These sponges are often saturated by soaking them in open pans of solution. Sometimes, sponges with attached handles are provided in a plastic pouch containing enough liquid to saturate the sponges.
While inexpensive, these techniques are messy and offer little control over inadvertent dripping of the solution into areas where it is undesired. Because many of the available solutions contain active ingredients such as alcohol and iodine, good control over the application has long been desirable.
Devices have been developed in an attempt to prevent the dripping of solution associated with these early techniques, and to reduce the time required for application of the antiseptic solution. In particular, the DURAPREP products commercially available from 3M Company of St. Paul, Minn. have enjoyed commercial success by providing substantially drip-free, convenient application. U.S. Pat. No. 4,925,327 describes a liquid applicator that incorporates a rigid, porous metering insert to regulate the flow rate of liquid disposed between the applicator handle and a foam sponge covering a major orifice of the handle. The liquid to be dispensed is contained in a rupturable reservoir removably affixed at the other major orifice of the handle.
U.S. Pat. No. 5,658,084 further discloses a liquid applicator in which the liquid is contained in a frangible ampoule inside the body of the applicator. This ampoule is supported and protected by a deformable element that prevents unintentional breakage of the ampoule from impacts during storage and handling before use. The applicator is actuated by pushing at least a portion of the frangible ampoule through an aperture in the deformable element and into contact with a means for breaking the ampoule.
Such ampoules are made of glass, in spite of the fact that sealed glass ampoules are relatively expensive. Many clinicians prefer to apply the prep in full aseptic attire (including sterile surgical gloves) and, therefore, it is important that the applicator that will be touched by those gloves be provided in a sterile condition. And since, for example, iodine based solutions decompose with exposure to gamma irradiation, manufacturers turn to gas sterilization with ethylene oxide gas to sterilize the outer surface of the container. Iodine solutions can form toxic by products such as iodohydrin (2-iodoethanol) when exposed to ethylene oxide sterilization, so they must be protected from exposure to this sterilant. Glass is a good barrier to agents such as ethylene oxide, unlike many other commonly used medical packaging materials, and so has been the material of choice for containing the prep solutions in spite of its cost.
While these described products have provided considerable advances, they are complex to manufacture, placing them beyond the means of some health care consumers. The art could still benefit from an applicator that could provide convenient, substantially drip-free dispensing of surgical preps at a lower cost.
The present invention provides a systems and methods for applying or dispensing surgical prep solution. Among the potential advantages of the systems and methods of the invention are the ability to dispense surgical prep solution substantially drip-free.
The applicator system includes a spreader element and a container of surgical prep solution. The spreader element preferably includes a body with at least one orifice covered by a pad. The orifice is in fluid communication with a passage through an elongated stem connected to the body.
The passage connects to a spout on the container when the surgical prep solution is to be dispensed. It may be preferred to angle the stem relative to the pad and, further, to provide a stem that is long enough to ensure that, if the applicator is used by a clinician with sterile gloved hands, the gloves do not come close to contacting the patient""s skin so as to contaminate the gloves and violate aseptic technique.
As used in connection with the present invention, xe2x80x9csurgical prep solutionxe2x80x9d includes skin and/or mucosa antiseptic compositions that may be useful for preparing the skin for other medical procedures such as the introduction of catheters, inoculations, etc. In some instances, surgical prep solutions used in connection with the invention may be film-forming when, e.g., applied to human or animal skin.
Surgical prep solutions used in connection with the present invention may include one or more of a variety of human skin-compatible antimicrobial agents. Examples of some suitable antimicrobial agents include, but are not limited to, chlorhexidine, triclosan, octenidene, quaternary ammonium functional surfactants, etc. It may be preferred, but not required, that the surgical prep solution include iodine or chlorhexidine in its composition. It may further be preferred that the surgical prep solution include alcohol in its composition. One suitable surgical prep solution may be, e.g., DURAPREP surgical prep solution available from 3M, St. Paul, Minn.
When using low viscosity surgical prep solutions (which may also be of relatively low surface tension), it may be preferred to provide a flow restrictor between the container and the pad. The flow restrictor partially restricts the flow of surgical prep solution from the container to the spreader element to enhance uniform filling of the pad with solution and reduce or prevent dripping. The flow restrictor may take a variety of forms as described below.
The container may, for example, be provided in a tube resembling a toothpaste tube. The container holds the surgical prep solution and includes a spout adapted to attach to the stem. It may be preferred that the container is rigid enough to act as a handle for the applicator system in combination with the stem.
The container is collapsible and compression of the container causes the surgical prep solution to flow from the container to the pad when the container is attached to the spreader element. The collapsible container preferably does not recover significantly when depressed.
This property of being collapsible without significant recovery can assist with the avoidance of dripping. Many commercially available containers are resilient and recover substantially all of their original volume after compression. In many instances this results in refilling of the container with air. If a recovered container is used, the clinician could be inspired to compress the container one or more additional times. The additional compression pushes air down the stem, which can force the surgical prep solution out of the pad, resulting in undesirable dripping. In addition to dripping, the air may also cause the surgical prep solution to foam.
As used in connection with the present invention, the collapsible containers provide an original volume when filled with surgical prep solution and before dispensing of the surgical prep solution. After dispensing of the surgical prep solution, the compressed containers can be described as having a collapsed volume less than the original volume. The collapsible containers of the present invention preferably recover about 50% or less (more preferably about 25% or less) of the difference between the original volume and the collapsed volume within 30 seconds of dispensing a majority of the surgical prep solution in the container.
It may be further preferred that the container be impermeable to ethylene oxide gas, which allows the container to be sterilized by conventional ethylene oxide sterilizers without allowing ethylene oxide to penetrate the container. Penetration of ethylene oxide into the container has the potential to create toxic products within the surgical prep solution. This may be especially true with surgical prep solutions including iodine, in which 2-iodoethanol (iodohydrin) can be formed with exposure to ethylene oxide.
Preferred impermeable containers do not allow more than 100 ppm ethylene oxide into the container during exposure to ethylene oxide gas during sterilization, preferably less than 50 ppm, more preferably less than 25, and most preferably less than 10 ppm. Ideally, the container is manufactured of materials that provide a complete barrier to ethylene oxide gas penetration (less than 1 ppm, which is the current detection limit).
Suitable containers for use in the present invention may preferably retain surgical prep solution even when aged at 50xc2x0 C. for 28 days with no more than, e.g., a 2 percent net weight loss. This can be especially difficult with hydroalcoholic surgical prep solutions. One potentially suitable material for the containers may be, e.g., polymer/aluminum foil laminates.
The container also includes a spout through which the surgical prep solution is delivered from the container to the spreader element. Although spouts in the form of threaded male members are disclosed in connection with the illustrative embodiments, it should be understood that spouts used in connection with the containers may alternatively take any suitable form that can cooperate with the spreader element to deliver surgical prep solution from the container to the pad.
The spout may preferably include a container seal formed over its opening. More preferably, the container includes a sealed spout that is impermeable to ethylene oxide, e.g., a polyolefin/foil laminate seal. The seal may preferably be opened as the container is engaged with the spreader element.
In preferred embodiments of the present invention, the system is unvented when the container is properly connected to the spreading element. As used herein, unvented means that the only opening into the fluid path is through the orifice in the spreader element body. With an unvented system, compression of the container causes the surgical prep solution to rapidly travel through the passage and into the pad. This can be faster and more convenient than waiting for gravity to move the surgical prep solution into the pad as in prior art vented applicators. Preferred unvented systems require compression of the container to dispense the surgical prep solution in sufficient amounts to wet the pad.
It may also be preferred that at least the exterior surfaces of the spreader element and the container be sterile such that the applicator system can be used in an aseptic manner to apply the surgical prep solution. This may necessarily require that the spreader element and container be provided in a sterile package.
In one aspect, the present invention provides an applicator system for surgical prep solution, the system including a spreader element and a collapsible container of surgical prep solution. The spreader element includes a body with an orifice; a pad attached to the body over the orifice; a stem comprising a distal end attached to the body and a passage extending between the distal end of the stem and a proximal end of the stem, wherein the passage is in fluid communication with the orifice at the distal end of the stem. The collapsible container includes surgical prep solution and a spout adapted to attach to the proximal end of the stem, wherein the surgical prep solution can be delivered to the passage for delivery to the pad. The collapsible container has an original volume and a collapsed volume after dispensing of the surgical prep solution. The collapsible container recovers about 50% or less of the difference between the original volume and the collapsed volume within 30 seconds of dispensing of a majority of the surgical prep solution.
In another aspect, the present invention provides method of applying surgical prep solution by providing a spreader element including a body having an orifice; a pad attached to the body over the orifice; a stem having a distal end attached to the body and a passage extending between the distal end of the stem and a proximal end of the stem, wherein the passage is in fluid communication with the orifice at the distal end of the stem. The method further includes providing surgical prep solution in a collapsible container; attaching the collapsible container to the proximal end of the stem, wherein the surgical prep solution is in fluid communication with the passage of the stem; and dispensing the surgical prep solution into the passage by compressing the collapsible container, wherein the collapsible container has an original volume and a collapsed volume after dispensing of the surgical prep solution, and further wherein the collapsible container recovers about 50% or less of the difference between the original volume and the collapsed volume within 30 seconds of dispensing a majority of the surgical prep solution.
In another aspect, the present invention provides a method of manufacturing an applicator system for surgical prep solution, the method including providing a spreader element that includes a body having an orifice; a pad attached to the body over the orifice; and a stem comprising a distal end attached to the body and a passage extending between the distal end of the stem and a proximal end of the stem, wherein the passage is in fluid communication with the orifice at the distal end of the stem. The method further includes providing a collapsible container including surgical prep solution and a spout adapted to attach to the stem of the spreader element, wherein the surgical prep solution can be delivered to the passage for delivery to the pad. The collapsible container has an original volume and a collapsed volume after dispensing of the surgical prep solution, and the collapsible container recovers about 50% or less of a difference between the original volume and the collapsed volume within 30 seconds of dispensing of a majority of the surgical prep solution.
In another aspect, the present invention provides an applicator system for surgical prep solution. The system includes a spreader element and a collapsible container attached to the spreader element. The spreader element includes a body with an orifice and a pad attached to the body over the orifice. The spreader element also includes a stem with a distal end attached to the body and a passage extending between the distal end of the stem and a proximal end of the stem, wherein the passage is in fluid communication with the orifice at the distal end of the stem. The collapsible container retains surgical prep solution therein (until dispensed) and has an original volume and a collapsed volume after dispensing of the surgical prep solution, and further wherein the collapsible container recovers about 50% or less of a difference between the original volume and the collapsed volume within 30 seconds of dispensing a majority of the surgical prep solution. The container may also include a container seal retaining the surgical prep solution within the collapsible container.
In another aspect, the present invention provides an applicator system for surgical prep solution, the system including a container retaining surgical prep solution therein and a spreader element. The spreader element includes a body having an orifice and a pad attached to the body over the orifice. The spreader element also includes a stem with a distal end attached to the body and a passage extending between the distal end of the stem and a proximal end of the stem, wherein the passage is in fluid communication with the orifice at the distal end of the stem. Further, the spreader element includes a receptacle at the proximal end of the stem, the receptacle extending around at least a portion of a circumference of the container when the container is attached to the spreader element.
These and other features and advantages of the present invention are described below in connection with various illustrative embodiments of the invention.